Thread: Garmin GB Discoverer 1:50K - Full Coverage (2.00)

Thats great but i've followed Post 193 and as i asked above once file is saved should it still read on file ext as a .TXT file?

Originally Posted by TMS

Thats great but i've followed Post 193 and as i asked above once file is saved should it still read on file ext as a .TXT file?

hi i had the same problem where it could not unlock the map on a garmin Colorado 300 and a 4gig card
when i checked the properties of the password file it was actually a gmapsupp.unl.txt file
you need to copy the key in the file, delete the file then use notepad to create a new file called gmapsupp.unl **make sure you have save as type' all files' selected or it will not work.*****
once it is created do not open it again and save it or it could change it back to a txt file even though it says gmapsupp.unl in the save bar.
make sure it is in the same directory as the map file (usually in a folder named garmin on the memory card.)
click on its propities again and make sure it does not show it as a txt file
after i did this map worked first time )))

I'm having trouble with my Colorado 300 and JetMouse. I'm assuming the Unit ID is the 9 digit code on the inside of the GPS. When I enter this, I don't see any option to select either my device from the software Product, nor the GB Discover option from the Map Product. Have I got the correct Unit ID?

Yes thats what i have done, But as i have asked twice now does it show as a .TXT file in the folder? As when i've copied the instructions thats what it shows as in the files list, Can anyone else please tell me?

Hello, first post -

I have been uploading some Discoverer files (1:50k full UK, 1:25k national parks) unlocked using Fast IMG Unlocker v2.1, and putting them on a microSD card onto my Edge 800 unit. It all seems to run smoothly except the 1:50k raster maps aren't visible for full UK.

1. Fast IMG Unlocker 2.1 doesn't come up with any error messages on the 2.19gb 1:50k file, and it updates the 'date modified' to the correct time.
2. The Edge 800 unit knows the 'Discoverer 1:50k' map is in there, and has it Enabled. (File name is gmapdisco.img or similar, this doesn't seem to make a difference)
3. With all other maps turned off, it displays the wide-scale rasters up to 1.2km scale; zooming from 800m upwards it then just shows the vectors of roads - so all this data is coming from the Discoverer 1:50k map (since all others turned off)

It seems rather odd.. has anyone else come accross this, or could suggest a remedy?


As a note, the 1:25k National Parks imagery works great with no issues, from files unlocked with Fast IMG Unlocker v2.1. Between the 300m - 800m zoom range it also displays 1:50k map data, though this is restricted to the area which then also contains the 1:25k data.

Many thanks in advance for any suggestions.

No, the code is a 10-digit code. The one you have is the serial number of the device. You can find the unit ID on several places - somewhere in the device diagnosis, in BaseCamp, etc. Have a look at the right threads (howtos) in this forum.

Oh my God! I downloaded it and now I realize it won't work on my Garmin Legend HCx! I suppose I'd better get a TOPO map? Thanks anyway...

Has anyone used gb discoverer on a nuvi 310, and if so how did you unlock it?